DHCP assistance needed

RouterOS General
1

Hi All, I need some help setting up DHCP on my routerboard RB750GL.
First off, been using them for a while now for QOS, bandwidth management and fire walling (version 5.2).

How my sites are setup:
Ether 1 connects to the Cisco Router.
Ether 2 connects to the main Cisco Switch.
Ether 5 is setup as management and also connected tot the main Cisco Swicth.

I have 2 Vlans (2 and 3) that come in via the router to the main Cisco switch on a trunk port.
Then on the Cisco Switch I have certain ports on Vlan 2 and others on Vlan 3 as it is 2 separated networks per site.
Now this has been working great for my existing sites because I have servers there etc.
Vlan 2 has domain controller, dhcp, exchange etc
Vlan 3 has domain controller, dhcp, etc

Ok so Vlan 2 is my admin domain and Ether 5 is also on vlan 2 with an IP which I use to connect and manage it.
I hope that give a picture of how my sites currently work.

Now, I have 3 new sites added to my network but there are no servers there and might not be for a while.
And I am not a big fan of static IP addresses !
I have setup my RB750’s (version 6.15), same as my old ones with trunk Ether 1 and Ether 2 and then management port Ether 5.

But now what I’m trying to do and not getting to work properly is to set up Ether 3 and Ether 4 for DHCP.
Ether 3 will be Vlan 2 and connected to the Cisco Switch on a vlan 2 port.
Ether 4 will be Vlan 3 and connected to the Cisco Switch on a vlan 3 port.
So in a nutshell I want Ether 3 to dish out IP addresses for Vlan 2 and then Ether 4 to dish out IP addresses for Vlan 3.
It is 2 separate subnets, one for each vlan.
Ether 3 and Ether 4 does not have to route traffic or anything, all they have to do is dish out IP addresses.

2

I have tried quite a few options now and still cannot get it to work properly.
Can anyone assist me ?

3

The best thing to do is make sure the interfaces have IP addresses on them, and then start the DHCP server wizard.

There’s a button “DHCP Setup” on the main tab of the DHCP Server screen. That launches a wizard which asks basic questions and ends up creating the elements you need:

IP Pool - from which the lease addresses are assigned
Network - from which the correct IP parameters / DHCP options are configured
Server instance - the actual instance of DHCP service. This is where you link it to the actual interface where the process will listen for requests.

Make sure your firewall input chain is not blocking the DHCP requests on your LAN interfaces.

4

Thanks ZeroByte, I have disabled all fire walling until the dhcp is sorted then I will enable and test afterwards.

Let me try the wizard again, maybe I have better luck after the long weekend :slight_smile: